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Background PCA3, a non-coding RNA, has been approved as a potential urinary biomarker for prostate cancer. However, PCA3 urine tests have some limitations. Therefore, we developed a colorimetric method for PCA3 detection in urine. Methods The assay was based on interactions between unmodified gold nanoparticles (AuNPs) and thiolated PCR products. Thiolated PCR products were amplified by RT-PCR using a thiol-labeled primer at the 5′ end. Thiolated products of PCA3 bound to the surface of AuNPs and led to the prevention of salt-induced aggregation (red color). In the absence of the PCR products, AuNPs changed their color from red to blue due to the salt-induced aggregation. These changes were detected by the naked eye and spectrophotometer. Results Our assay was specific for PCA3 in prostate cancer cell lines with a visual detection limit of 31.25 ng/reaction. The absorption ratio 520/640 nm was linear against PCR product concentration (R2 = 0.9798) in the reaction. This method is promising for discrimination of prostate cancer patients from both healthy controls and benign prostatic hyperplasia patients according to their urinary PCA3 expression levels. Conclusions This study established a simple, rapid, sensitive and specific assay for PCA3 detection which may be applicable for prostate cancer diagnosis.

Overexpression of free radicals in the brain is emerging as important markers in the etiology of neurodegenerative diseases including Parkinson’s disease, Alzheimer’s disease, and stroke. Numerous antioxidants with protective effect on neuronal injuries under oxidative stress are often limited to penetrate the blood–brain barrier (BBB). Angiopep-2 is the ligand of low-density lipoprotein receptor-related protein expressed on the BBB possessing high transcytosis capacity and parenchymal accumulation. In this study, novel Angiopep-conjugated p-coumaric acid (3) was synthesized, using the Click chemistry, as a potential antioxidant for the protection of the brain under oxidative stress. The clickable Angiopep (3) was synthesized by Cu(I)-catalyzed 1,3-dipolar cycloaddition reaction of the terminal acetylene-modified Angiopep and azide of p-coumaric acid. The Angiopep-conjugated compound (3) showed antioxidant potency and non-cytotoxic effect toward brain endothelial cells (BECs). Obviously, the penetration and BECs protection of 3 were higher than that of the unconjugated p-coumaric acid. The results establish the bio-conjugation of antioxidant and Angiopep with enhanced protective effect on the BECs under oxidative stress. The findings provide great potential for the development of neurotherapeutics with increased brain penetration.

Heterocyclic compounds like 8-hydroxyquinoline (8HQ) and derivatives have been found in natural products and therapeutics. Herein 8HQ and metal complexes of 8HQ-5-substituted (X) uracils, X = I, NO2 (1-6) were investigated for their antimicrobial potency. The complexes 1-6 exhibited growth inhibition against many strains of gram-positive and gram-negative bacteria with minimum inhibitory concentrations (MICs) of 575.71-718.76 mu M. The investigated compound 8HQ was shown to be a very strong antimicrobial agent with the MIC of 27.58 mu M that comparable to ampicillin (MIC 26.93 mu M), the reference drug. The activity of 8HQ mostly was observed for resistant pathogens, gram- positive bacteria e.g. Staphylococcus aureus, Enterococcus faecalis and diploid fungus, Candida albicans. The findings reveal 8HQ as the very potent antimicrobial agent and a series of 8HQ transition metal complexes as novel antimicrobials as well as the applications of 8HQ for the design and synthesis of new and potential therapeutic lead compounds.

In this paper, we present a new modular approach to immobilize boronic acid ligands that can offer effective separation of glycoproteins. A new "clickable" boronic acid ligand was synthesized by introducing a terminal acetylene group into commercially available 3-aminophenyl boronic acid. The clickable ligand, 3-(prop-2-ynyloxycarbonylamino)phenylboronic acid (2) could be easily coupled to azide-functionalized hydrophilic Sepharose using Cu(I)-catalyzed 1,3-dipolar cycloaddition reaction under mild condition. Compared to other boronic acid affinity gels, the new affinity gel displayed superior effectiveness in separating model glycoproteins (ovalbumin and RNase B) from closely related bovine serum albumin and RNase A in the presence of crude Escherichia coli proteins. Because of the simplicity of the immobilization through "click chemistry", the new ligand 2 is expected to not only offer improved glycoprotein separation in other formats, but also act as a useful building block to develop new chemical sensors for analysis of other glycan compounds.

Superoxide anions are reactive oxygen species that can attack biomolecules such as DNA, lipids and proteins to cause many serious diseases. This study reports the synthesis of copper complexes of nicotinic acid with related pyridine derivatives. The copper complexes were shown to possess superoxide dismutase (SOD) and antimicrobial activities. The copper complexes exerted SOD activity in range of 49.07-130.23 microM. Particularly, copper complex of nicotinic acid with 2-hydroxypyridine was the most potent SOD mimic with an IC(50) of 49.07 microM. In addition, the complexes exhibited antimicrobial activity against Bacillus subtilis ATCC 6633 and Candida albicans ATCC 90028 with MIC range of 128-256 microg/mL. The SOD activities were well correlated with the theoretical parameters as calculated by density functional theory at the B3LYP/LANL2DZ level of theory. Interestingly, the SOD activity of the copper complexes was demonstrated to be inversely correlated with the electron affinity, but was well correlated with both HOMO and LUMO energies. The vitamin-metal complexes described in this report are great examples of the value-added benefits of vitamins for medicinal applications.

Molecular imprinting is a technology that facilitates the production of artificial receptors toward compounds of interest. The molecularly imprinted polymers act as artificial antibodies, artificial receptors, or artificial enzymes with the added benefit over their biological counterparts of being highly durable. In this study, we prepared molecularly imprinted polymers for the purpose of binding specifically to tocopherol (vitamin E) and its derivative, tocopherol acetate. Binding of the imprinted polymers to the template was found to be two times greater than that of the control, non-imprinted polymers, when using only 10 mg of polymers. Optimization of the rebinding solvent indicated that ethanol-water at a molar ratio of 6:4 (v/v) was the best solvent system as it enhanced the rebinding performance of the imprinted polymers toward both tocopherol and tocopherol acetate with a binding capacity of approximately 2 mg/g of polymer. Furthermore, imprinted nanospheres against tocopherol was successfully prepared by precipitation polymerization with ethanol-water at a molar ratio of 8:2 (v/v) as the optimal rebinding solvent. Computer simulation was also performed to provide mechanistic insights on the binding mode of template-monomer complexes. Such polymers show high potential for industrial and medical applications, particularly for selective separation of tocopherol and derivatives.

In the previous studies, the cytotoxicities of anthranilate sulfonamides were investigated. Herein, the bioactivities of 4-substituted (X = NO2, OCH3, CH3, Cl) benzenesulfonamides of anthranilic acid (5-8) are reported. The results revealed that all sulfonamides selectively exerted antifungal activity (25-50 % inhibition) against C. albicans at 4 μg/mL. Furthermore, compounds 6 and 8 show antioxidative (SOD) activity. These sulfonamides, except for 6, selectively display cytotoxic effects toward MOLT-3 cells. It is interesting to note that sulfonamides with electron withdrawing substituent (5, X = NO2) exhibited the highest cytotoxicity. This study provided preliminary structure-activity relationship of the anthranilic sulfonamides that is useful for further in-depth investigation.

Nicotinic acid (also known as vitamin B3) is a dietary element essential for physiological and antihyperlipidemic functions. This study reports the synthesis of novel mixed ligand complexes of copper with nicotinic and other select carboxylic acids (phthalic, salicylic and anthranilic acids). The tested copper complexes exhibited superoxide dismutase (SOD) mimetic activity and antimicrobial activity against Bacillus subtilis ATCC 6633, with a minimum inhibition concentration of 256 microg/mL. Copper complex of nicotinic-phthalic acids (CuNA/Ph) was the most potent with a SOD mimetic activity of IC(50) 34.42 microM. The SOD activities were observed to correlate well with the theoretical parameters as calculated using density functional theory (DFT) at the B3LYP/LANL2DZ level of theory. Interestingly, the SOD activity of the copper complex CuNA/Ph was positively correlated with the electron affinity (EA) value. The two quantum chemical parameters, highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO), were shown to be appropriate for understanding the mechanism of the metal complexes as their calculated energies show good correlation with the SOD activity. Moreover, copper complex with the highest SOD activity were shown to possess the lowest HOMO energy. These findings demonstrate a great potential for the development of value-added metallovitamin-based therapeutics.

The aim of this study was to survey for the current rate of Giardia lamblia infection in three different districts in two provinces of Thailand, Surin and Samut Sakhon, in March 2002, October 2003, and March 2004. Two districts are rural areas and another is sub-urban. Volunteers of any age from Surin Province and children aged between 5 to 7 years old from three secondary schools in Samut Sakhon were enrolled for the stool examination. The method used was stool examination by both simple smear and normal saline concentration technique on fresh collected feces. All samples were tested in duplicate. Out of 3,358 healthy individuals from rural Surin Province, 75 cases (2.2%) were found positive for G. lamblia, 30 of which were below 10 years of age. By comparison, 656 individuals from sub-urban Samut Sakhon Province volunteered and 43 (6.5%) were positive for G. lamblia. Other intestinal parasites, both helminth and protozoa, were also identified from these two groups: hookworm, Enterobius vermicularis, Strongyloides stercoralis, Trichuris trichiura, Taenia species, Entamoeba histolytica, Entamoeba coli, Endolimax nana, and Blastocystis hominis. From this study, the data showed that parasitic infection acquired via fecal-oral route is still a significant problem for these two provinces of Thailand.